For Over Flanders Fields Phase 3,
beta testing is complete and the game has been printed up for
distribution! This third installment, called "Between Heaven and
Hell", promises loads of new stuff: new AI, flight models, campaign engine, high resolution environment, and quick combat.

Winder let us know today that the game was shipped to the publisher just yesterday and presumably a batch of DVDs came back today:

Guys just to let you all know that the P3 V1.0 DVD was sent to the UK
for the start of publishing yesterday via speed courier - it arrived
today 25hours later - yeah impressive.

No I have no idea when you will be able to purchase P3 but I can say the product is ready and its AWESOME.